BIM 101: How Total Station Layout Benefits Construction Contractors

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Total stations enable contractors to measure angles and distances extremely accurately for laying out new construction and as-builting existing construction using discrete points. Available in both manual and robotic options, they use a solid well-proven technology that originated in distance measurement applications for the military. They have been used in surveying and engineering applications for many years. Now, these same instruments and technologies are being adapted for the construction industry.

Made for Construction

The majority of contractors have entered BIM with multidisciplinary coordination. Design information from architects or engineers in a 2D or 3D format is combined with fabrication models or drawings from subcontractors to create a “federated model”—a digital twin that reflects exactly what is to be built in the field. This combined model is used to identify constructability and building issues so solutions can be developed digitally before they become problems in reality on the construction site. Models are updated throughout the construction process with as-built field data to minimize unforeseen changes.

Digital layout solutions born out of the surveying industry bridge the gap between the coordinated model in the office and physical construction in the field. Modern total stations designed for construction applications are simple in design and easy to operate with minimal training. They allow the contractor to take very accurate, coordinated data directly from a model and digitally project it or replicate it on a jobsite for a “paint-by-numbers” installation, which accelerates both installation speed and accuracy by connecting the total station to the BIM process. Connecting BIM and digital layout is a win-win for the construction industry.

It’s a far cry from tape measures and strings, which leave a substantial amount of room for human error. Using total station technology makes jobs much easier and more efficient while providing the accuracy needed to successfully extend BIM from the office to the job site.

What is your biggest challenge in moving from traditional layout to robotic total station layout? Share your comments below.

1 comment

Our biggest challenge is establishing reliable control points to set up our total station. If the concrete contractor or surveyor lays out the slab edges accurately, this is fairly straightforward. Unfortunately, these are not always precise and no other reliable points within the building are available until after concrete is poured and the framer is laying out walls. In addition, the structural engineer’s slab edge plan will frequently have slightly different dimensions than the architect’s plan due to errors made throughout the design process as the building footprint was adjusted for various reasons. These seemingly minor differences, often fractions of an inch, make setting up a total station nearly impossible.

As a plumbing contractor, we benefit greatly from this technology when it can be properly utilized (particularly when locating sleeves and anchors to be cast in place in post-tensioned concrete slabs). The full potential of this technology will only be realized when general contractors get more proactive about coordinating the efforts of all trades involved. Slight modifications to workflows and scheduling may be required, but overall the time and money saved with total stations far outweighs these small changes.